There is interest in methods for the synthesis of large numbers of diverse compounds which can be screened for various possible physiological or other activities. Techniques have been developed in which one adds individual units sequentially as part of the chemical synthesis to produce all or a substantial number of the possible compounds which can result from all the different choices possible at each sequential stage of the synthesis. For these techniques to be successful, it is necessary for the compounds to be amenable to methods by which one can determine the structure of the compounds so made. Brenner and Lerner (PNAS USA 81: 5381-83 (1992)) and WO 93/20242, for example, describe a synthesis wherein oligonucleotides are produced in parallel with and are chemically linked as genetic tags to oligopeptides as the compounds of interest. WO 93/06121 teaches methods for particles-based synthesis of random oligomers wherein identification tags on the particles are used to facilitate identification of the oligomer sequence synthesized. A detachable tagging system is described in Ohlmeyer et al., Proc. Natl. Acad. Sci. USA, 90, 10922-10926, December 1993.